The first sign of a breakthrough yesterday was the release of Jalal Sharafi, an Iranian diplomat abducted from the streets of Baghdad two months ago, whom Iran claimed had been seized by Iraqi commandos controlled by the US. At the same time, an Iraqi Foreign Ministry official said the Iraqi government was "intensively" seeking the release of five Iranian officials captured in a US helicopter raid on a long-established Iranian liaison office in the Kurdish capital of Arbil in January.

The rhetoric in Tehran and London became more diplomatic as Tony Blair said the next two days would be "fairly critical" in resolving the crisis, though the Prime Minister gave no details. Iran continues to deny it seized the British naval detachment in the northern Persian Gulf on 23 March to force an exchange of hostages, while Britain said it would not bargain for their release.

The seizure of the sailors and marines was the latest episode in a series of tit-for-tat confrontations between the US and Iran which began, as The Independent revealed yesterday, when the US tried to seize senior Iranian intelligence officials on an official visit to Arbil on 11 January. The raid failed and only succeeded in detaining five Iranian officials at the liaison office, which has now been officially recognised as a consular office.

Senior Kurdish officials told
The Independent newspaper that the real US targets were Mohammed Jafari, the powerful deputy head of the Supreme National Security Council, and General Minojahar Frouzanda, the head of intelligence of the Iranian Revolutionary Guards. They had visited President Jalal Talabani of Iraq at Dokan near Sulaimaniyah and then gone on to Arbil where they saw Massoud Barzani, president of the Kurdistan regional government, at his headquarters outside the city.

The Arbil raid came a few hours after an aggressive address to the nation by President George Bush, in which he denounced Iran as America's great enemy in Iraq. It has been followed by a series of tit-for-tat incidents such as the attempted abduction of five US soldiers in a highly sophisticated attack near the holy city of Kerbala, south of Baghdad, in which the assailants first tried to take prisoner the US soldiers but later killed them. The US blamed the episode on Iraqi Shias acting as proxies for Iran.

Though there was greater optimism yesterday about the British hostages being released, the Iranians have a tradition of blowing hot and cold in negotiations and drawing them out to extract the last possible advantage from the situation.

The release of Mr Sharafi is a hopeful sign. He was seized in mysterious circumstances on 4 February by uniformed men. Iran and some Shia politicians in Baghdad said they were from the 36th Commando Unit of the Iraqi Army that was, in practice, controlled by the US. Mr Sharafi has now returned to Tehran. The US denies any role in his disappearance. At the same time, immediately after the Arbil raid, the US Secretary of State, Condoleezza Rice, revealed that President Bush had approved a policy of raiding Iranian targets on Iraqi soil.

Neither Mr Sharafi, a second secretary at the embassy, nor the five Iranian officials seized in Arbil seem to have been important figures. Mr Sharafi was involved in plans to open a branch of the Iranian national bank in Baghdad. One of the captives from Arbil was described by the US as a senior officer of the Quds Force, an elite unit of Iran's Revolutionary Guards.

American and British claims that there was no connection between the capture of Iranian officials on 11 January and the seizure of the British sailors and marines was undermined yesterday when the Iraqi Foreign Ministry official said his government was also working "intensively" for the release of those five other Iranians to "help in the release of the British sailors and marines".

In Washington, President Bush signalled the same: "I also strongly support the Prime Minister's declaration that there should be no quid pro quos when it comes to the hostages," he said.

With the stand-off at a sensitive stage, Britain reacted with caution to the release yesterday of a new picture of the captives on the website of Iran's Fars News Agency, an apparent breach of the understanding that no more such photographs would be published. The picture, apparently a still taken from a video, showed six sailors squatting on a carpet in a room, wearing blue, black and red tracksuits.

Britain had expressed outrage over the airing of videos of the service personnel last week. The British also froze most diplomatic contacts with Iran. On Monday, an Iranian state-run television station said all 15 of the Britons had confessed to entering Iranian waters illegally.

How the world reacted to our story

John Nichols, writing on The Nation magazine's blog

"President Bush describes Iran's seizure of 15 British sailors and marines as "inexcusable behaviour". But did the Bush administration's anti-Iran machinations lead to the escalation in tensions that culminated in the seizure of the Brits? One of the finest reporters on Middle East affairs argues that this is precisely the case."

USA Today (website)

"A British newspaper is reporting that Iran seized 15 British sailors in retaliation for a botched attempt by US forces to capture two high-ranking Iranian officials while they were visiting the Kurdish portion of Iraq earlier this year. 'Early on the morning of 11 January, helicopter-borne US forces launched a surprise raid on a long-established Iranian liaison office in the city of Arbil in Iraqi Kurdistan. They captured five relatively junior Iranian officials whom the US accuses of being intelligence agents and still holds,' Patrick Cockburn reports in
The Independent."

Fox News (website)

"A botched attempt by the US to abduct two senior Iranian officials on a visit to Iraq 10 weeks ago was the flashpoint for the current crisis in which [Iran] detained 15 British troops in the Persian Gulf,
The Independent reported. The US move happened on the morning of January 11, when forces carried out a surprise raid on an established Iranian liaison's office in northern Iraq, the newspaper claimed."

Mother Jones (liberal magazine)

"This is precisely how wars get started, an act of aggression by one side followed by an act of retaliation by the other, tit for tat until someone gets nuked. Patrick Cockburn reports that Iran's capture of 15 British marines and sailors was a direct response to a botched US operation in January, when the military snatched 5 Iranians in Arbil - identified as members of a Revolutionary Guard, or Pasdaran, unit - who were suspected of arming insurgents."

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